Abū Bakr, ‘Abd al-Qāhir ibn ‘Abd ar-Raḥmān ibn Muḥammad al-Jurjānī (1009 – 1078 or 1081 AD [400 – 471 or 474 A.H.]); nicknamed "Al-Naḥawī" (the grammarian), he was a renowned Persian grammarian of the Arabic language, literary theorist of the Muslim Shafi'i, and a follower of al-Ash'ari. He wrote several celebrated works on grammar and rhetoric, among these are Mi,ut Ạmil and Al-Jumal - introductions to Arabic syntax - and a commentary titled Al-Mughnī in three volumes.Al-Jurjānī is said to have never left his native town of Gorgan, Iran, yet his reputation in the twin sciences of ilm al balaghah (eloquence and rhetorical art) and ilm al bayan (a branch of Arabic rhetoric dealing with metaphorical language), reached many Arabic scholars who travelled to see him. His two books on these subjects, Asrār al-Balāghah (Secrets of Rhetoric), and Dalāʾīl al-ʿIjāz fi-l-Qurʾān (Arguments of the Miraculous Inimitability of the Quran) show influences of al-Jurjānī's predecessors, the grammarian Sibawayh, the critic Abi Helal al-'Askari al Balaghi, and the linguist and literary theorist Abu Ali al-Farisi, the author of al-Idah (Elucidation). Ali al-Farisi's nephew, Abi al-Hussein Muhammad ibn al-Hassan ibn Abd al-Wareth al-Faressi al-Nawawi, was al-Jurjānī's teacher, under whom he studied the al-Idah, and on which he wrote a thirty-volume work of commentary entitled al Maghna fi Sharh al-Idah . Source: Wikipedia (en)